title: Spectral changes in spontaneous MEG activity across the lifespan.
abstract: OBJECTIVE
  The aim of this study is to explore the spectral patterns of spontaneous magnetoencephalography (MEG) activity across the lifespan.
  
  
  METHODS
  Relative power (RP) in six frequency bands (delta, theta, alpha, beta-1, beta-2 and gamma) was calculated in a sample of 220 healthy subjects with ages ranging from 7 to 84 years.
  
  
  RESULTS
  A significant RP decrease in low-frequency bands (i.e. delta and theta) and a significant increase in high bands (mainly beta-1 and beta-2) were found from childhood to adolescence. This trend was observed until the sixth decade of life, though only slight changes were found. Additionally, healthy aging was characterized by a power increase in low-frequency bands. Our results show that spectral changes across the lifespan may follow a quadratic relationship in delta, theta, alpha, beta-2 and gamma bands with peak ages being reached around the fifth or sixth decade of life.
  
  
  CONCLUSIONS
  Our findings provide original insights into the definition of the 'normal' behavior of age-related MEG spectral patterns. Furthermore, our study can be useful for the forthcoming MEG research focused on the description of the abnormalities of different brain diseases in comparison to cognitive decline in normal aging.
authors.affiliation: Biomedical Engineering Group, E.T.S. Ingenieros de Telecomunicación, University of Valladolid, Valladolid, Spain.
authors.forename: Carlos
authors.initials: C
authors.lastname: Gómez
authors.forename: Jose M
authors.initials: JM
authors.lastname: Pérez-Macías
authors.forename: Jesús
authors.initials: J
authors.lastname: Poza
authors.forename: Alberto
authors.initials: A
authors.lastname: Fernández
authors.forename: Roberto
authors.initials: R
authors.lastname: Hornero
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D001921:Brain / Q000502:physiology*; D002648:Child; D005260:Female; D006801:Humans; D008136:Longevity / Q000502:physiology*; D015225:Magnetoencephalography / Q000639:trends*; D008297:Male; D008875:Middle Aged; D055815:Young Adult